JP5198120B2 - Hard coat film and resin molded product - Google Patents

Description

  The present invention relates to a hard coat film and a resin molded product using the same.

  A hard coat film for insert molding in which a metal vapor-deposited film or a printed layer is formed on one surface of a base film and a hard coat layer serving as a surface protective layer is formed on the other surface of the base film is known ( Patent Documents 1 and 2).

JP 2005-288720 A Japanese Patent Laying-Open No. 2005-305786

  By the way, generally, the hard coat layer used for the purpose of protecting the surface of the molded product is required to have a hard coat property. For example, a hardness of not less than H in pencil hardness and a load of not less than 300 g in steel wool test is required. For this reason, a hard-coat layer is normally comprised with curable resin excellent in hard-coat properties, such as an electron beam curable resin and an ultraviolet curable resin.

  However, when the hard coat films described in Patent Documents 1 and 2 are used for actual insert molding, cracks, whitening, and cracks are likely to occur on the surface of the hard coat layer during molding. In general, since the surface of a molded product is curved or has corners, it is difficult to avoid the occurrence of cracks.

  On the other hand, it is also conceivable to increase the flexibility of the hard coat layer by adding a thermoplastic resin to the resin component constituting the hard coat layer. However, in this case, there is a problem that the hard coat property of the hard coat layer is deteriorated and the load of the steel wool test described above cannot be endured.

  The problem to be solved by the invention is to provide a hard coat film having sufficient hard coat properties and crack resistance. Another object of the present invention is to provide a resin molded product obtained by integrating the hard coat film.

  This invention solves the said subject by adjusting suitably the hard-coat property of the hard-coat layer formed in the at least one surface of a base film.

  According to the said invention, since the hard-coat property of the hard-coat layer is adjusted appropriately, it can be equipped with sufficient hard-coat property and crack resistance.

  Hereinafter, embodiments of the invention will be described with reference to the drawings.

《Hard coat film》
As shown in FIG. 1, the hard coat film 10 according to this embodiment has a hard coat layer 12 laminated on one surface of a base film 11.

  The hard coat layer 12 of this example has its hard coat property adjusted appropriately. Specifically, the Martens hardness (HM) and the plastic hardness (Hupl) are adjusted to be larger than specific values, and the indentation elastic modulus (corresponding to Young's modulus) EIT is adjusted to be smaller than the specific value.

  The present inventor studied focusing on a specific index related to the hard coat property of the hard coat layer 12 in order to achieve both the conflicting performances of hard coat property and crack resistance. As a result, the Martens hardness and the plastic hardness were low. By adjusting the hard coat property of the hard coat layer 12 so as to be larger than the specific value and the indentation elastic modulus smaller than the specific value, the above-mentioned hard coat property and crack resistance can be made compatible. I found what I can do. Since the hard coat layer 12 of this example is appropriately adjusted in its hard coat properties, it can be provided with sufficient hard coat properties and crack resistance.

  Martens hardness (HM) represents the hardness (hardness of dent) of the hard coat layer 12 obtained from the test load and the indentation surface area when the surface of the hard coat layer 12 is pressed with a Vickers indenter. It becomes an index of surface hardness.

In this example, the value of HM of the hard coat layer 12 is preferably 250 N / mm ² or more, more preferably 280N / mm ² or more, more preferably it is adjusted to 300N / mm ² or more. By adjusting the HM of the hard coat layer 12 to a predetermined value or more, generation of scratches on the hard coat layer 12 is effectively prevented. On the other hand, if the HM of the hard coat layer 12 is too large, problems such as film warping may occur. For this reason, in this example, the HM of the hard coat layer 12 is preferably adjusted to 500 N / mm ² or less, more preferably 400 N / mm ² or less.

  The value of HM in this example was determined by using an ultra-micro hardness tester (Fischer Instruments, trade name: Fisher Scope HM2000) under an atmosphere of 20 ° C. and 60% relative humidity. It is the value which measured the hardness of the surface of the hard-coat layer 12 by the method based on 14577-1. However, the maximum test load is a value measured at 1 mN.

  The plastic hardness (Hupl) represents the hardness (hardness of indentation) of the hard coat layer 12 obtained from the indentation depth after unloading of the Vickers indenter, and is an index of the hardness of the hard coat layer 12.

In this example, Hupl of the hard coat layer 12 is preferably 800 N / mm ² or more, more preferably 900 N / mm ² or more, more preferably it is adjusted to 1000 N / mm ² or more. By adjusting the Hupl of the hard coat layer 12 to a predetermined value or more, generation of scratches on the hard coat layer 12 is effectively prevented. On the other hand, if the Hupl of the hard coat layer 12 is too large, problems such as film warping may occur. For this reason, in this example, it is desirable that the Hupl of the hard coat layer 12 is adjusted to preferably 3000 N / mm ² or less, more preferably 2000 N / mm ² or less.

  In addition, the value of Hupl can be measured by a method based on ISO-14477-1, and can be calculated by the following equation (3). In the following formula, calculation formulas (1) and (2) for universal hardness (Hu) are shown together with Hupl.

[Expression 1] Hu = F / (A (h)) = F / (26.43 × h ² ) (1)
[Expression 2] A (h) = [(4 × sin (a / 2)) / (cos ² (a / 2))] × h ² (2)
[Expression 3] Hupl = (F _max /(26.43×hr ² )) (3)
Here, in the formulas (1) to (3), “F” is the test load (unit: N), “F _max ” is the maximum value of the test load (unit: N), and “A (h)” is the indenter. Is the surface area (unit: mm ² ) in contact with the object to be measured.

A (h) is calculated from the shape of the indenter and the indentation depth. When the indenter is a Vickers indenter, it is calculated as (26.43 × h ² ) from the angle a (136 °) of the facing surface of the pyramidal intruder. Is done. “H” is the indentation depth when the test load is applied (unit: mm), “h _max ” is the maximum value of the indentation depth when the test load is applied (unit: mm), and “hr” is the hF curve. The h coordinate value (unit: mm) of the h-axis intersection of the tangent at the (h _max , F _max ) point.

The hF curve is shown in FIG. 2, for example. (1) in FIG. 2 is an hF curve when the load is weighted from 0 to _Fmax , and (2) is an hF curve when the load is subsequently gradually unloaded from _Fmax to 0. (3) is a tangent at the (h _max , F _max ) point of the hF curve.

  In addition, the value of Hupl in this example is a value obtained by measuring the hardness of the surface of the hard coat layer 12 by a method based on ISO-14477-1 under the measurement conditions described later using the same apparatus as in the case of HM described above. It is.

  Measurement conditions are, for example, indenter shape: Vickers indenter (a = 136 °), measurement environment: temperature 20 ° C., relative humidity 60%, maximum test load: 1 mN, load speed: 1 mN / 20 seconds, maximum load creep time: 5 Second, unloading speed: 1 mN / 20 seconds. For each sample, a total of 15 points, that is, 5 points at equal intervals in the axial direction and 3 points at equal angles in the circumferential direction, are measured, and the average value is defined as the plastic hardness (Hupl) in this example.

  The indentation elastic modulus (Young's modulus) EIT represents the ease of bending (flexibility) of the hard coat layer 12 and is an index of the brittleness of the hard coat layer 12.

  In this example, the EIT of the hard coat layer 12 is preferably adjusted to 5000 MPa or less, more preferably 4900 MPa or less. By adjusting the EIT of the hard coat layer 12 to a predetermined value or less, the hard coat layer 12 is easily bent and contributes to improvement of crack resistance. On the other hand, if the EIT of the hard coat layer 12 is too small, the hard coat property tends to be lowered. For this reason, in this example, the EIT of the hard coat layer 12 is preferably adjusted to 4000 MPa or more, more preferably 4300 MPa or more.

  In addition, the value of EIT is a value equivalent to the Young's modulus measured according to ISO-14477-1 using the same apparatus as in the case of HM and Hupl described above, and the hard coat layer 12 is formed on the stainless steel plate. The Young's modulus of the hard coat layer 12 itself measured using the obtained hard coat layer 12, that is, measured in a state not affected by the elastic modulus of the base film 11. However, as with HM and Hupl, it is a value measured at a maximum test load of 1 mN.

  The value of the bending resistance test of the hard coat film 10 of this example varies depending on the thickness of the hard coat layer 12 and the type and thickness of the base film 11, but is preferably adjusted to 5 mm or less, more preferably 4 mm or less. It is desirable. The crack resistance of the hard coat layer 12 can be improved by adjusting the value of the bending resistance test to a predetermined value or less. In addition, the value of a bending test is a value measured by the cylindrical mandrel method based on JIS-K5600-5-1 (1999).

  It is desirable that the hard coat layer 12 of this example is adjusted so as not to cause scratches when steel wool # 0000 with a load of 300 g is reciprocated 10 times. By adjusting in this way, it is possible to ensure the necessary hard coat properties.

  In the hard coat layer 12 of this example, the pencil scratch value (pencil hardness) is preferably adjusted to H or more. More preferably, it is adjusted to 2H or more. By adjusting the pencil scratch value to a predetermined value or more, it is possible to effectively prevent the surface of the hard coat layer 12 from being scratched. The pencil scratch value is a value measured by a method based on JIS-K5400 (1990).

  The thickness of the hard coat layer 12 of this example is preferably 10 μm or less, more preferably 5 μm or less. This is because if the thickness exceeds 10 μm, cracks and the like are likely to occur. On the other hand, if the thickness is too thin, sufficient hard coat properties may not be exhibited. Therefore, the thickness of the hard coat layer 12 is preferably 0.5 μm or more, more preferably 1 μm or more.

  The hard coat layer 12 of this example can be obtained, for example, by preparing a paint, applying it to the base film 11 and curing it.

  The paint that can be used in this example contains a resin component. The resin component includes an ionizing radiation curable resin.

  As the ionizing radiation curable resin contained in the resin component, a photopolymerizable prepolymer that is crosslinked and cured by irradiation with ionizing radiation (ultraviolet rays or electron beams) can be used. In this example, the photopolymerizable prepolymer described later may be used alone, or two or more kinds may be used in combination.

  The photopolymerizable prepolymer includes a cationic polymerization type and a radical polymerization type.

  Examples of the cationic polymerization type photopolymerizable prepolymer include epoxy resins and vinyl ether resins. Examples of the epoxy resin include bisphenol epoxy resin, novolac epoxy resin, alicyclic epoxy resin, and aliphatic epoxy resin.

  As the radical polymerization type photopolymerizable prepolymer, an acrylic prepolymer (hard prepolymer) having two or more acryloyl groups in one molecule and having a three-dimensional network structure by crosslinking and curing is hard coat property. In view of the above, it is particularly preferably used.

  Examples of the acrylic prepolymer include urethane acrylate, polyester acrylate, epoxy acrylate, melamine acrylate, polyfluoroalkyl acrylate, and silicone acrylate.

  The urethane acrylate prepolymer can be obtained, for example, by esterifying a polyurethane oligomer obtained by reaction of polyether polyol or polyester polyol with polyisocyanate by reaction with (meth) acrylic acid. Examples of the polyester acrylate-based prepolymer include esterification of a hydroxyl group of a polyester oligomer having hydroxyl groups at both ends obtained by condensation of a polyvalent carboxylic acid and a polyhydric alcohol with (meth) acrylic acid, or a polyvalent carboxylic acid. It can be obtained by esterifying the terminal hydroxyl group of an oligomer obtained by adding an alkylene oxide to an acid with (meth) acrylic acid. The epoxy acrylate prepolymer can be obtained, for example, by esterification by a reaction of an oxirane ring of a relatively low molecular weight bisphenol type epoxy resin or novolac epoxy resin with (meth) acrylic acid.

  The acrylic prepolymer can be appropriately selected according to the type and application of the object to be coated (base film 11). The acrylic prepolymer can be used alone, but it is preferable to add a photopolymerizable monomer in order to impart various performances such as improvement of cross-linking curability and adjustment of curing shrinkage.

  Examples of the photopolymerizable monomer include monofunctional acrylic monomers (for example, 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, butoxyethyl acrylate, etc.), bifunctional acrylic monomers (for example, 1,6-hexanediol diacrylate). , Neopentyl glycol diacrylate, diethylene glycol diacrylate, polyethylene glycol diacrylate, hydroxypivalate ester neopentyl glycol diacrylate, etc.) and trifunctional or higher acrylic monomers (eg dipentaerythritol hexaacrylate, trimethylpropane triacrylate, pentaerythritol tris) Acrylate etc.). “Acrylate” includes not only acrylate but also methacrylate. These photopolymerizable monomers may be used alone or in combination of two or more.

  The total content (in terms of solid content) of the photopolymerizable prepolymer and the photopolymerizable monomer in the paint of this example is preferably 40 to 99% by weight, more preferably 60 to 95% by weight, in all resin components. More preferably, it is 80 to 90% by weight.

  In particular, in this example, in order to achieve both hard coat properties and crack resistance of the formed film, the ionizing radiation curable resin includes at least a specific photopolymerizable prepolymer (A) and a photopolymerizable monomer (B). It is preferable to contain any of them.

Particular photopolymerizable prepolymers (A), having a dendrimer structure in the molecule include polyfunctional oligomers having three or more (meth) click Relate functionality.

  The dendrimer structure means a shape in which monomers are polymerized while branching and spread radially, and a polyfunctional oligomer having a dendrimer structure is represented by the general formula (1).

具体的には、アミノ基、水酸基、カルボキシル基、フェニル基、エチレンオキサイド基、ビニル基、プロピレンオキサイド基などの官能基を有し、末端に（メタ）アクリレート官能基を有するものである。なかでも溶媒への溶解性や取扱性および他の電離放射線硬化型樹脂を加える場合にはその樹脂との相溶性等の観点から、エチレンオキサイド基を含有し、末端に（メタ）アクリレート官能基を有するものが好ましい。

Specifically, an amino group, a hydroxyl group, a carboxyl group, a phenyl group, an ethylene oxide group, a vinyl group, a functional group such as propylene oxide groups are those terminated with (meth) click Relate functionality. Among them solubility and handling properties of the solvent and in the case of adding other ionizing radiation curable resin from the viewpoint of compatibility of the the resin, contain ethylene oxide groups, the terminal (meth) click Relate functional Those having a group are preferred.

(Meth) as the molecular weight of the number and oligomers of A click Relate functional groups is large, the hardness of the hard coat layer 12 formed by the ionizing radiation curable resin composition is high, cracks are less likely to occur during molding. However, the crack resistance during molding is reduced and too large number of (meth) click Relate functionality. If the molecular weight of the oligomer is too large, the hard coat property of the hard coat layer 12 is lowered. Thus, (meth) click Relate the number of functional groups is preferably 3 to 10, more preferably 5-8. Moreover, molecular weight becomes like this. Preferably it is 1000-3000, More preferably, it is 1500-2000.

  The content of the photopolymerizable prepolymer (A) in the coating material of this example is preferably 10 to 160 parts by weight, more preferably with respect to 100 parts by weight in total of the photopolymerizable monomer and other photopolymerizable prepolymers. 20 to 100 parts by weight, more preferably 30 to 70 parts by weight. By setting the content of the photopolymerizable prepolymer (A) to 10 parts by weight or more, it is possible to prevent cracks and the like from being generated in the edge portion when pressed during molding. Moreover, hard coat property can be maintained by setting it as 160 weight part or less.

  Examples of the specific photopolymerizable monomer (B) include a photopolymerizable monomer having a cyclo ring together with a polymerizable reactive group in the molecule.

  The cyclo ring includes at least one element selected from the group consisting of carbon, nitrogen, oxygen and silicon, and is preferably a 5-membered ring or a 6-membered ring. Specific examples of the cyclo ring structure include cycloolefins such as cyclopentene and cyclohexene, tetrahydrofuran, 1,3-dioxane, ε-caprolactone, ε-caprolactam, silacyclopentene, cyclodecane, isobonyl and the like. As monomers having such a cyclo ring structure, ε-caprolactone-modified tris- (2-acryloxyethyl) isocyanurate, ε-caprolactone-modified tris- (2-hydroxyethyl) isocyanurate, dimethylol tricyclodecanedi (meta ) Acrylate, isobornyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, 2-acryloyloxyethyl hexahydrophthalic acid and the like.

  The content of the photopolymerizable monomer (B) in the coating material of this example is preferably 1 to 70 in terms of solid content with respect to the entire photopolymerizable prepolymer and photopolymerizable monomer constituting the ionizing radiation curable resin. % By weight, more preferably 5 to 50% by weight. By setting the content to 1% by weight or more, generation of cracks and the like during pressurization can be prevented. Moreover, the fall of the hard-coat property of the hard-coat layer 12 can be prevented by setting it as 70 weight% or less.

  In addition, when (B) is contained together with the above-described photopolymerizable prepolymer (A), the total content of (A) and (B) is such that other photopolymerizable monomers and other photopolymerizable prepolymers are contained. Preferably it is 20-200 weight part with respect to a total of 100 weight part of a polymer, More preferably, it is 30-160 weight part, More preferably, it is 40-140 weight part. Although the total content of (A) and (B) varies depending on the thickness of the hard coat layer 12 and the like, it cannot be generally stated. For example, when the thickness of the hard coat layer 12 is in the range of 2 to 5 μm, (A) And (B) becomes like this. Preferably it is 10-90 weight% with respect to the total content of (B), More preferably, it is 15-60 weight%, More preferably, you may be 20-40 weight%. By setting the content of (B) to 10% by weight or more, cracks and the like can be more unlikely to occur in the edge portion when pressed during molding. Moreover, it can prevent that hard-coat property falls by setting it as 80 weight% or less.

  When the hard coat layer 12 of this example is formed by being cured by ultraviolet irradiation, additives such as a photopolymerization initiator, a photopolymerization accelerator, and an ultraviolet sensitizer are added to the paint of this example. Is preferably blended.

  As the photopolymerization initiator, for radical polymerization type photopolymerizable prepolymers and photopolymerizable monomers, for example, acetophenone, benzophenone, Michler ketone, benzoin, benzylmethyl ketal, benzoylbenzoate, α-acyloxime ester, thioxanthones, etc. Is mentioned. Examples of the photopolymerization initiator for the cationic polymerization type photopolymerizable prepolymer include oniums such as aromatic sulfonium ions, aromatic oxosulfonium ions, and aromatic iodonium ions, tetrafluoroborate, hexafluorophosphate, hexafluoroantimonate, The compound which consists of anions, such as hexafluoroarsenate, is mentioned. These may be used alone or in combination of two or more. Examples of the photopolymerization accelerator include p-dimethylaminobenzoic acid isoamyl ester and p-dimethylaminobenzoic acid ethyl ester. Examples of the ultraviolet sensitizer include n-butylamine, triethylamine, and tri-n-butylphosphine.

  In the paint of this example, in addition to the ionizing radiation curable resin as a binder component, other resins such as a thermoplastic resin and a thermosetting resin are about 30% by weight or less of the resin constituting the hard coat layer 12. If it can be included. In addition, the compounding quantity of the other resin which can be contained may differ with the kind of ionizing radiation curable resin. When the thermosetting resin is contained, a thermopolymerizable monomer or prepolymer is used alone or in combination, and if desired, a thermopolymerization initiator, that is, a compound that generates active radical species by heating, or the like is contained. Examples of the thermal polymerization initiator include peroxides and azo compounds. Specific examples include benzoyl peroxide, t-butyl-peroxybenzoate, azobisisobutyronitrile, and the like.

  Moreover, you may mix | blend an additional component suitably with the coating material of this example as needed. Examples of the additive component include a matting agent for imparting an antiglare function, a colorant, an antistatic agent, and an ultraviolet absorber.

  When the paint of this example is an organic solvent-based paint, it may be appropriately selected depending on the type of the resin component, but the above-described resin component (additional component if necessary) is dissolved in a diluting solvent such as an organic solvent. After the dispersion, the paint of this example can be produced by adding an additive as necessary. The organic solvent is not particularly limited, but alcohols (eg, methanol, ethanol, isopropanol, butanol, octanol, etc.), ketones (eg, acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone, cyclohexanone, etc.), esters (eg, acetic acid) Ethyl, butyl acetate, ethyl lactate, γ-butyrolactone, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, etc.), ethers (eg, ethylene glycol monomethyl ether, diethylene glycol monobutyl ether, etc.), aromatic hydrocarbons (eg, benzene) , Toluene, xylene, etc.) and amides (for example, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, etc.).In the case of using a solvent-free paint, the paint of this example can be obtained by adding an additive component to the resin component described above as necessary.

  The base film 11 is preferably one having excellent transparency, heat resistance and mechanical strength. Specifically, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polycarbonate, polyethylene, polypropylene, polystyrene, triacetyl. Examples thereof include cellulose, acrylic, polyvinyl chloride, norbornene compounds. In particular, from the viewpoint of good dimensional stability due to heat, it is preferable to use a biaxially stretched polyethylene terephthalate film.

  Even if the base film 11 is subjected to a surface treatment such as an easy adhesion treatment in order to improve the adhesion with the hard coat layer 12, the metal vapor deposition layer 13, the printing layer 14, or the adhesive layer 15 described later. Good.

  The base film 11 may contain additives similar to the additives that can be contained in the paint of this example, including pigments and ultraviolet absorbers.

  The thickness of the base film 11 is not particularly limited, but is 20 to 200 μm, preferably about 50 to 150 μm, in consideration of handleability and mechanical strength.

  The coating (coating) of the paint on the base film 11 may be performed by a conventional method, for example, bar coating, die coating, blade coating, spin coating, roll coating, gravure coating, flow coating, dip coating, spray coating, screen printing, Brush coating etc. can be mentioned.

  In this example, the coating film after coating is applied so that the thickness described above is obtained after drying and curing described below. If the coating material of this example is applied to the base film 11, it is preferable to dry the coated film at about 50 to 120 ° C.

  Curing of the paint can be performed by irradiating the coated film after application with heat curing and / or ionizing radiation (light).

  When using heat, as the heat source, for example, an electric heater, an infrared lamp, hot air, or the like can be used.

  In the case of ionizing radiation (light), the radiation source is not particularly limited as long as it can cure the coating film applied to the base film 11 in a short time. For example, examples of infrared ray sources include lamps, resistance heating plates, and lasers. Examples of the visible light source include sunlight, a lamp, a fluorescent lamp, and a laser. Ultraviolet (ionizing radiation) radiation sources include ultra-high pressure mercury lamps, high pressure mercury lamps, low pressure mercury lamps, carbon arcs, metal halide lamps, and the like. Ultraviolet rays in a wavelength region of 100 nm to 400 nm, preferably 200 nm to 400 nm, emitted from such an ultraviolet ray source are irradiated. Examples of the electron beam (ionizing radiation) source include scanning and curtain electron beam accelerators. An electron beam having a wavelength region of 100 nm or less emitted from such an electron beam accelerator is irradiated.

The dose of ionizing radiation varies depending on the type of ionizing radiation. For example, in the case of ultraviolet rays, the amount of light is preferably about 100 to 500 mJ / cm ² , and in the case of electron beams, it is preferably about 10 to 1000 krad.

  The hard coat layer 12 of this example manufactured as described above has both hard coat properties (scratch resistance) and crack resistance. The crack resistance is exhibited while maintaining the hard coat property. When external pressure (bending force or tensile force) is applied, the pressure is absorbed by the dendrimer structure in the molecule, or the cycloid in the molecule is absorbed. It is considered that pressure is absorbed by deformation of the ring structure, and in any case, cracks are prevented from occurring on the layer surface.

  Since the hard coat film 10 of this embodiment has both hard coat properties and crack resistance, for example, an operation unit (keypad) of a device such as a touch panel of a home appliance, a mobile phone, a game machine, a sound player, or a notebook computer. Part), etc., and can be applied to decoration and surface protection of various molded products (particularly resin molded products) (suitable for insert molding applications).

  Moreover, since the hard coat film 10 has both hard coat properties and crack resistance, it is not only used for integral molding at the time of insert molding, but also for other purposes such as glass scattering prevention and punching such as membrane switches. It can be used for applications that require processes such as processing and bending. This is because when the hard coat film 10 is used at the time of punching, no cracks, cracks or the like are generated at the edge portion, and even when used at the time of bending, cracks, whitening, cracks, or the like do not occur.

  For example, the hard coat film 10 is also useful when the keypad portion of a mobile phone is formed of a hard coat film instead of a resin molded product. This is because it has both hard coat properties and crack resistance.

  In this embodiment, for example, when a molded product made of a resin or the like is molded with a mold, the resin and the entire hard coat film are integrally molded by molding, A hard coat film used for the purpose of obtaining a resin molded product having a pattern and a surface protective layer formed thereon is referred to as an “insert molding film”.

  When the hard coat film 10 of this embodiment is used for insert molding, the basic configuration is the base film 11 and the hard coat layer 12 described above, and further, the hard coat film 10 is molded on the other surface of the base film 11. The decoration layer for decorating goods may be laminated | stacked.

  As a decorating layer, it can be comprised by the metal vapor deposition layer 13 formed in the other surface of the base film 11, and the printing layer 14 laminated | stacked on this metal vapor deposition layer 13, for example. An adhesive layer 15 may be laminated on the decorative layer.

  For example, after the metal vapor deposition layer 13 is formed on the other surface of the base film 11, the decorative layer is formed by removing a part of the metal vapor deposition layer 13 by etching and removing the metal vapor deposition layer 13. Or after forming a desired character or pattern on the substrate film 11 by a known printing method, silk screen method, gravure method, ink jet method or the like, and forming a metal vapor deposition layer 13 thereon. It can be formed by a technique. There is a case where the printing layer 14 is omitted and the metal vapor deposition layer 13 is formed directly on the base film 11, or there is a case where only the printing layer 14 does not have the metal vapor deposition layer 13. When providing the printing layer 14, you may provide the receiving layer for receiving printing ink in the surface in which the printing layer 14 of the base film 11 is provided.

  The metal deposition layer 13 is made of a metal such as aluminum, nickel, gold, platinum, chromium, iron, copper, tin, indium, silver, titanium, lead, or zinc, or an alloy or compound thereof by a known method such as vacuum. It can be formed by forming a film by vapor deposition, sputtering, ion plating, or the like.

  The adhesive layer 15 is a layer provided to improve the adhesion between the molded article material and the metal vapor deposition layer 13, and is polyurethane, polyacrylic, polyester, epoxy, polyacetic acid depending on the material of the molded article material. Vinyl-based, vinyl chloride / vinyl acetate copolymer, cellulose-based adhesives and the like can be used as appropriate.

《Method for manufacturing resin molded product》
Next, an example of a method for decorating a resin molded product and protecting the surface using the hard coat film 10 of this example as an insert molding film will be described.

  First, when the hard coat film 10 of this example is made into a resin molded product, the hard coat layer 12 is arranged and pressed so that the hard coat layer 12 is on the outside, and is molded into a desired shape.

  Next, with the hard coat film 10 molded so that the hard coat layer 12 is in contact with the inner wall surface placed in one mold, the mold is clamped with the other mold to form a cavity inside the mold. To do.

  Next, after the resin material heated and fluidized is poured into the cavity in the mold, the resin material is cured and a resin molded product integrated with the hard coat film 10 is obtained.

The molding conditions (temperature, mold clamping pressure, time) are appropriately selected according to the resin (molding material), the shape of the molded product, and the like. In general, the mold clamping pressure is calculated by molding product projection area × in-mold resin pressure. As an example, when the resin to be injection-molded is ABS resin and the molded product size (L × W × H) is 60 × 80 × 2 (mm ³ ), the mold clamping pressure is 60 t, the mold temperature is 60 ° C., and the resin temperature is 250 ° C. The injection speed is 60 mm / second. The resin may be any resin that can be injection molded. For example, an acrylic resin, a thermoplastic resin such as a polycarbonate resin, an ABS resin, or an AS resin, or a thermosetting resin is used. The resin is cured and integrated with the hard coat film 10 to obtain the resin molded product of this example.

  In this example, since the hard coat film 10 of this example provided with the hard coat layer 12 having excellent crack resistance is used as the insert molding film, cracks are generated at the time of pressing the hard coat film 10 and molding by a mold. The resin molded product produced (decoration and surface protection) has excellent aesthetics and excellent hard coat properties.

  Examples of the resin molded product include a touch panel of a home electric appliance, a mobile phone, a game machine, an audio player, and an operation unit (keypad unit) of a device such as a notebook computer.

  Next, examples that further embody the above-described embodiment of the present invention will be given and described in more detail. “Parts” and “%” are based on weight unless otherwise indicated.

<< Experiment 1 >>
First, a coating solution for a hard coat layer was prepared.

<Coating liquid for hard coat layer>
Dendrimer structure polyfunctional oligomer A1 8 parts (solid content 100%) (Miramer SP1114: MIWON)
-Photopolymerizable polymer / photopolymerizable monomer 12 parts (100% solids) (Beamset 575: Arakawa Chemical Industries)
-Photopolymerization initiator 0.6 part (Irgacure 651: Ciba Japan)
45 parts of propylene glycol monomethyl ether Next, the prepared coating liquid for hard coat layer was applied to one surface of a 125 μm-thick polyester film (Cosmo Shine A4300: Toyobo Co., Ltd.) as the base film 11 by a bar coater method. After drying, ultraviolet rays were irradiated with a high-pressure mercury lamp (irradiation amount 400 mJ / cm ² ) to form a hard coat layer 12 having a thickness of 3 μm to obtain a film sample.

  About the obtained film sample, the Martens hardness (HM), the plastic hardness (Hupl), the indentation elastic modulus (Young's modulus), and the hard coat property (steel wool resistance (SW) resistance) of the hard coat layer 12 by the following methods. And pencil hardness), crack resistance and pencil hardness were evaluated. The results are shown in Table 1.

  (1) “Martens hardness (HM)”, (2) “plastic hardness (Hupl)” and (3) “Young's modulus” are both ultra-micro hardness test equipment (Fischer Instruments, (Trade name: Fischer Scope HM2000), and the hardness and Young's modulus of the surface of the hard coat layer 12 were measured under the measurement conditions described later by a method based on ISO-14477-1.

  The measurement conditions for all of (1), (2) and (3) were as follows.

Indenter shape: Vickers indenter (a = 136 °),
Measurement environment: temperature 20 ° C, relative humidity 60%,
Maximum test load: 1 mN
Loading speed: 1 mN / 20 seconds,
Maximum load creep time: 5 seconds,
Unloading speed: 1 mN / 20 seconds.

  (4) Regarding “SW resistance”, first, the surface of the hard coat layer 12 is rubbed 10 times with steel wool # 0000 with a load of 300 g. Next, the presence or absence of scratches on the surface of the hard coat layer 12 is visually observed. As a result, it was evaluated as “◎” for those that were not scratched, “◯” for those that were hardly scratched, and “×” for those that were clearly scratched.

  (5) About "pencil hardness", the pencil scratch value of the film sample surface was measured by the method based on JIS-K5400 (1990). The measured values obtained are “◎” when the measured value is 2H or higher, “◯” when the measured value is H or higher and lower than 2H, and a plurality of samples are prepared in the same experimental example. Those that were less than or equal to “Δ” were evaluated, and those that were less than H were evaluated as “×”.

  (6) “Crack resistance” is based on flex resistance (cylindrical mandrel method) in accordance with JIS-K5600-5-1 (1999). Each piece is folded back and wound so that 12 is on the outside, and whether or not the hard coat layer 12 in the wound portion is cracked is visually observed. As a result, the case where cracks could not be confirmed was evaluated as “◎”, the case where few cracks were confirmed as “◯”, the case where slight cracks were confirmed as “Δ”, and the case where clear cracks were confirmed as “×”.

<< Experiment 2 >>
A film sample was obtained by preparing a coating solution under the same conditions as in Experimental Example 1 except that the coating solution for hard coat layer prepared by the following formulation was used. Measurements and evaluations similar to those in Experimental Example 1 were performed. The results are shown in Table 1.

<Coating liquid for hard coat layer>
Ε-Captolactone-modified tris- (2-hydroxyethyl) isocyanurate 5 parts (SR368: Sartoma Company) (solid content 100%)
-10 parts of photopolymerizable polymer / photopolymerizable monomer (beam set 575: Arakawa Chemical Industries) (solid content 100%)
・ 0.4 parts of photopolymerization initiator (Irgacure 651: Ciba Japan)
Propylene glycol monomethyl ether 30 parts << Experimental example 3 >>
A coating solution was prepared under the same conditions as in Experimental Example 1, except that dendrimer structure polyfunctional oligomer A2 (NK ester A-HBR5: Shin-Nakamura Chemical Co., Ltd.) was used instead of dendrimer structure polyfunctional oligomer A1. A sample was obtained. Measurements and evaluations similar to those in Experimental Example 1 were performed. The results are shown in Table 1.

<< Experimental Example 4 >>
A coating solution was prepared under the same conditions as in Experimental Example 1 except that the blending amount of the dendrimer structure polyfunctional oligomer A1 was 12 parts and the blending amount of the photopolymerizable polymer / photopolymerizable monomer was 8 parts. Obtained. Measurements and evaluations similar to those in Experimental Example 1 were performed. The results are shown in Table 1.

<< Experimental Example 5 >>
A coating solution was prepared under the same conditions as in Experimental Example 1 except that the blending amount of the dendrimer structure polyfunctional oligomer A1 was 4 parts and the blending amount of the photopolymerizable polymer / photopolymerizable monomer was 16 parts. Obtained. Measurements and evaluations similar to those in Experimental Example 1 were performed. The results are shown in Table 1.

<< Experimental Example 6 >>
The blending amount of ε-captolactone-modified tris- (2-hydroxyethyl) isocyanurate (hereinafter referred to as “cyclocyclic structure reactive monomer”) is 1 part, and the blending amount of photopolymerizable polymer / photopolymerizable monomer is 14 parts. A coating solution was prepared under the same conditions as in Experimental Example 2 except that the film sample was used. Measurements and evaluations similar to those of Experimental Example 2 were performed. The results are shown in Table 1.

<< Experimental Example 7 >>
A coating solution was prepared under the same conditions as in Experimental Example 2, except that the amount of the cyclocyclic structure reactive monomer was 10 parts and the amount of the photopolymerizable polymer / photopolymerizable monomer was 5 parts. Obtained. Measurements and evaluations similar to those of Experimental Example 2 were performed. The results are shown in Table 1.

<< Experimental Example 8 >>
A coating solution was prepared under the same conditions as in Experimental Example 1 except that the dendrimer structure polyfunctional oligomer A1 was not blended (0 part) and the blending amount of the photopolymerizable polymer / photopolymerizable monomer was 20 parts. A sample was obtained. Measurements and evaluations similar to those in Experimental Example 1 were performed. The results are shown in Table 1.

Experimental Example 9
A film sample was obtained by preparing a coating solution under the same conditions as in Experimental Example 1 except that the coating solution for hard coat layer prepared by the following formulation was used. Measurements and evaluations similar to those in Experimental Example 1 were performed. The results are shown in Table 1.

<Coating liquid for hard coat layer>
-Thermoplastic acrylic resin (solid content 40%) 15 parts (Acridic A195: Dainippon Ink & Chemicals, Inc.)
・ Photopolymerizable polymer / photopolymerizable monomer 14 parts (100% solid content) <Beam Set 575: Arakawa Chemical Industries, Ltd.)
・ 0.4 parts of photopolymerization initiator (Irgacure 651: Ciba Japan)
Propylene glycol monomethyl ether 36 parts << Experimental example 10 >>
A coating solution was prepared under the same conditions as in Experimental Example 9, except that 20 parts of Agridic A195, 12 parts of Beamset 575, and 33 parts of propylene glycol monomethyl ether were used. A sample was obtained. Measurements and evaluations similar to those in Experimental Example 9 were performed. The results are shown in Table 1.

<< Experimental Example 11 >>
The coating liquid of Experimental Example 4 was prepared to obtain a film sample on which the hard coat layer 12 having a thickness of 1 μm was formed. Measurements and evaluations similar to those in Experimental Example 4 were performed. The results are shown in Table 1.

表１の結果から以下のことが確認できた。

From the results in Table 1, the following could be confirmed.

  First, regarding the hard coat properties (SW resistance and pencil hardness), when the HM or Hupl of the hard coat layer 12 is less than a predetermined value (Experimental Examples 9 to 11), the hard coat properties tend to decrease. . In addition, as in Experiment 9, even when HM is greater than or equal to a predetermined value, if Hupl is less than the predetermined value, the pencil hardness is better than Experiments 10 and 11, but from Experiments 1 to 8. In addition, the SW resistance tends to be lower than those of Experimental Examples 1 to 8. Further, as in Experimental Example 11, when HM is less than a predetermined value even if Hupl is greater than or equal to a predetermined value, the SW resistance is good, but since the hard coat layer 12 is thin, the pencil hardness is low. Not enough. On the other hand, sufficient hard coat property is obtained about Experimental Examples 1-8.

  Next, regarding crack resistance, when the EIT of the hard coat layer 12 exceeds a predetermined value (Experimental Example 8), the crack resistance tends to decrease. On the other hand, sufficient crack resistance is obtained about Experimental Examples 1-7 and 9-11.

  From these results, in the present experimental example, those having sufficient hard coat properties and crack resistance are Experimental Examples 1 to 7, and among them, Experimental Examples 1 to 3 are particularly excellent. It could be confirmed. That is, in the film samples of Experimental Examples 1 to 3, it was confirmed that the hard coat property and the crack resistance can be achieved at a high level.

<< Experimental Examples 12-14 >>
Injection mold (cell-phone) so that the hard coat layer is the outside when the film sample having a thickness of 3 μm of the hard coat layer obtained in Experimental Example 1, Experimental Example 8 and Experimental Example 10 is a resin molded product. The cover case mold (size: approx. 50 mm x 100 mm) is molded into a three-dimensional shape by vacuum molding, then the molten acrylic resin is filled into the mold, the mold is cooled, and integrated with the film sample The cured acrylic resin molded product was taken out. About these resin molded products, the edge part (curved surface and corner | angular part) of the resin molded product surface was observed visually. Moreover, the same evaluation as the film sample mentioned above was performed about the hard coat property of the surface of these resin molded products,
As a result, the resin molded product using the film sample of Experimental Example 1 had no cracks or whitening at the edge portion, and the same good results as the above film sample were obtained with respect to the hard coat property.

  On the other hand, with respect to the resin molded product using the film sample of Experimental Example 8, good results were obtained with respect to the hard coat property, but generation of cracks and whitening were confirmed at the edge portion.

  In addition, for the resin molded product using the film sample of Experimental Example 10, the edge portion was neither cracked nor whitened, but the hard coat property was inferior to that of the resin molded product of Experimental Example 1. .

FIG. 1 is a cross-sectional view showing a hard coat film according to an example of the invention. FIG. 2 is a graph showing an example of the hF curve.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Hard coat film 11 ... Base film 12 ... Hard coat layer 13 ... Metal vapor deposition layer 14 ... Print layer 15 ... Adhesive layer

Claims (8)

A hard coat film having a hard coat layer on at least one surface of the base film,
Curing of the ionizing radiation curable resin composition comprising a polyfunctional oligomer having a dendrimer structure, having 3 to 10 (meth) acrylate functional groups and a molecular weight of 1000 to 3000. Each value of Martens hardness, plastic hardness, and indentation elastic modulus when measured under the condition that the maximum test load is 1 mN is Martens hardness : 250 N / mm ² or more, plastic hardness : 800 N / mm ² or more, indentation elastic modulus : 5000 MPa or less, Hard coat film characterized by the above-mentioned. 2. The hard coat film according to claim 1, wherein the polyfunctional oligomer having a dendrimer structure is in a range of 10 parts by weight or more and 160 parts by weight or less with respect to 100 parts by weight of the ionizing radiation curable resin composition excluding it. A hard coat film, which is contained in the ionizing radiation curable resin composition .   The hard coat film according to claim 1 or 2, wherein the value of a bending resistance measured by a cylindrical mandrel method according to JIS-K5600-5-1 (1999) is 5 mm or less. Coat film.   4. The hard coat film according to claim 3, wherein the hard coat layer does not cause scratches when steel wool # 0000 with a load of 300 g is reciprocated 10 times.   The hard coat film according to claim 1, wherein the hard coat layer has a thickness of 0.5 to 10 μm.   6. The hard coat film according to claim 1, wherein at least one layer including a metal vapor deposition layer, a printing layer, and an adhesive layer is formed on the other surface of the base film. Hard coat film. A molded product formed by integrating a molding material and an insert molding film by molding,
The resin molded product, wherein the insert molding film is the hard coat film according to any one of claims 1 to 6.   The resin molded product according to claim 7, wherein the molding material is an acrylic resin or a polycarbonate resin.

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